<template>
  <div class="type-nav">
    <div class="container">
      <div @mouseleave="leaveSort" @mouseenter="sortShow">
        <h2 class="all">全部商品分类</h2>
        <transition name="sort">
          <div class="sort" v-show="sortIsShow">
            <div class="all-sort-list2" @click="goSearch">
              <div class="item" v-for="(c1,index) in categoryList" :key="c1.categoryId">
                <h3 :class="currentIndex==index?'activeBg':''" @mouseenter="activeBg(index)">
                  <a href="" :data-category1id="c1.categoryId">{{ c1.categoryName }}</a>
                </h3>
                <div class="item-list clearfix" :style="{display:currentIndex===index?'block':'none'}">
                  <div class="subitem" v-for="(c2,index) in c1.categoryChild" :key="c2.categoryId">
                    <dl class="fore">
                      <dt>
                        <a href="" :data-category2id="c2.categoryId">{{ c2.categoryName }}</a>
                      </dt>
                      <dd>
                        <em v-for="(c3,index) in c2.categoryChild" :key="c3.categoryId">
                          <a href="" :data-category3id="c3.categoryId">{{ c3.categoryName }}</a>
                        </em>
                      </dd>
                    </dl>
                  </div>
                </div>
              </div>
            </div>
          </div>
        </transition>
      </div>
      <nav class="nav">
        <a href="###">服装城</a>
        <a href="###">美妆馆</a>
        <a href="###">尚品汇超市</a>
        <a href="###">全球购</a>
        <a href="###">闪购</a>
        <a href="###">团购</a>
        <a href="###">有趣</a>
        <a href="###">秒杀</a>
      </nav>
    </div>
  </div>

</template>

<script>
import {mapActions, mapState} from "vuex";

export default {
  name: "TypeNav",
  data() {
    return {
      currentIndex: -1,   //通过动态修改索引添加激活背景类名
      sortIsShow: true,       //控制显示隐藏“全部商品分类”
    }
  },
  methods: {
    ...mapActions(['home/reqCategoryList']),
    // 节流激活背景
    activeBg(index) {
      let timer = null;
      if (timer) {
        return
      } else {
        timer = setTimeout(() => {
          this.currentIndex = index;
          timer = null;
        }, 50)
      }
    },
    //   不采用声明式导航router-link替换A标签进行路由跳转，因为router-link是一个组件 生成过多组件很消耗内存，所以通过事件委派编程式导航
    goSearch(e) {
      e.preventDefault()
      //  判断点击的标签是否为a标签
      if (e.target.tagName === 'A') {
        let {category1id,category2id,category3id} = e.target.dataset;
        let query = {categoryName: e.target.innerHTML};
        // 判断点击的是几级id
        if(category1id){
          query.category1Id = category1id;
        }else if(category2id){
          query.category2Id = category2id;
        }else if (category3id){
          query.category3Id = category3id;
        }
        let location = {name: 'search', query};
        if (Object.keys(this.$route.params).length !== 0) location.params = this.$route.params; // 判断是否有params参数，如果存在则一起携带
        this.$router.push(location)
      } else {
        if (e.target.tagName === 'H3') {  //如果点击的是H3标签则获取到
          console.log(e.target.children[0].dataset.categoryid);
        }
      }
    },
    sortShow() {
      if (this.$route.path === '/search') {
        this.sortIsShow = true;
      }
    },
    leaveSort() {
      this.currentIndex = -1;
      if (this.$route.path === '/search') {
        this.sortIsShow = false;
      }
    }
  },
  computed: {
    ...mapState('home', ['categoryList'])
  },
  mounted() {
    // 判断 如果是当前路由路径为search 则默认隐藏sort列表
    if (this.$route.path === '/search') {
      this.sortIsShow = false;
    }
  }
}
</script>

<style scoped lang="less">
.type-nav {
  border-bottom: 2px solid #e1251b;

  .container {
    width: 1200px;
    margin: 0 auto;
    display: flex;
    position: relative;

    .all {
      width: 210px;
      height: 45px;
      background-color: #e1251b;
      line-height: 45px;
      text-align: center;
      color: #fff;
      font-size: 14px;
      font-weight: bold;
    }

    .nav {
      a {
        height: 45px;
        margin: 0 22px;
        line-height: 45px;
        font-size: 16px;
        color: #333;
      }
    }

    .sort {
      position: absolute;
      left: 0;
      top: 45px;
      width: 210px;
      height: 461px;
      position: absolute;
      background: #fafafa;
      z-index: 999;


      .all-sort-list2 {
        .item {
          h3 {
            line-height: 30px;
            font-size: 14px;
            font-weight: 400;
            overflow: hidden;
            padding: 0 20px;
            margin: 0;

            a {
              color: #333;
            }

          }

          .activeBg {
            background: skyblue;
          }

          .item-list {
            display: none;
            position: absolute;
            width: 734px;
            min-height: 460px;
            background: #f7f7f7;
            left: 210px;
            border: 1px solid #ddd;
            top: 0;
            z-index: 9999 !important;

            .subitem {
              float: left;
              width: 650px;
              padding: 0 4px 0 8px;

              dl {
                border-top: 1px solid #eee;
                padding: 6px 0;
                overflow: hidden;
                zoom: 1;

                &.fore {
                  border-top: 0;
                }

                dt {
                  float: left;
                  width: 54px;
                  line-height: 22px;
                  text-align: right;
                  padding: 3px 6px 0 0;
                  font-weight: 700;
                }

                dd {
                  float: left;
                  width: 415px;
                  padding: 3px 0 0;
                  overflow: hidden;

                  em {
                    float: left;
                    height: 14px;
                    line-height: 14px;
                    padding: 0 8px;
                    margin-top: 5px;
                    border-left: 1px solid #ccc;
                  }
                }
              }
            }
          }
        }
      }
    }

    .sort-enter {
      height: 0;
    }

    .sort-enter-to {
      height: 461px;
    }

    .sort-enter-active {
      transition: all .5s linear;
    }
  }
}


</style>